I'm using After Effects CS5.5 and I have a problem using Particular. I have made musical notes that cross a path created by a light called Motion Path 1, like it should be. The first couple of particles cames all together in a wheel.

In this image you can see the problem. In yellow is the path. In red there are two other particles that make the same thing.

The only solution I found is to turn off the "orient along path" setting, but it brings a result I don't need. What do you think is happening?

This is all about birth rate, life span, velocity, and the other emitter properties. Seeing your timeline and the particular properties in your screenshot would help a lot. I can't tell anything about any of your settings or the path from this screenshot.

Try something like this:

With everything set to zero this setup leaves a string of textured polygons exactly along the path of the light I named Emitter.

Thanks Rick. But in that project you don't have activated the orient to path property niether is a Motion Path. I'm sure that if you do it the first particle will do the same thing. I have patched a little the problem moving the keyframes of the Motion Path light. With this the rotation of the first particle is done out of the screen, but still there.